Question : 301 redirect non-www to www

I am using the following to redirect http://mysite.com to http://www.mysite.com. I want to ensure that I'm doing it correctly and that it's a "permanent" redirect. (I'm still very new to such things.) It is working properly, I just want to make sure it's the correct way to do it.

RewriteEngine On
 
RewriteCond %{HTTP_HOST} ^mysite.com [NC]
RewriteRule ^(.*)$ http://www.mysite.com/$1 [L,R=301]

Answer : 301 redirect non-www to www

I would do it with a slight change:

RewriteCond %{HTTP_HOST} ^mysite.com$ [NC]
RewriteRule .? http://www.mysite.com%{REQUEST_URI} [R=301,L]

HTH